Retrospective Study
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Jul 26, 2021; 9(21): 5860-5872
Published online Jul 26, 2021. doi: 10.12998/wjcc.v9.i21.5860
Development and validation of a prognostic nomogram for colorectal cancer after surgery
Bo-Wen Li, Xiao-Yu Ma, Shuang Lai, Xin Sun, Ming-Jun Sun, Bing Chang
Bo-Wen Li, Shuang Lai, Xin Sun, Bing Chang, Department of Gastroenterology, The Frist Hospital of China Medical University, Shenyang 110000, Liaoning Province, China
Xiao-Yu Ma, Ming-Jun Sun, Department of Gastroenterology and Endoscopy, The Frist Hospital of China Medical University, Shenyang 110000, Liaoning Province, China
Author contributions: Li BW performed the research and wrote the paper; Ma XY supervised the report; Lai S and Sun X contributed to the analysis; Sun MJ and Chang B proposed the idea and clinical advice.
Supported by Science and Technology Support Program of Shenyang, No. 20-205-4-094.
Institutional review board statement: The experimental data are from the Surveillance, Epidemiology, and End Results (SEER) database, not clinical cases from any medical institutions. Therefore, our research does not need to be approved by an ethics committee.
Informed consent statement: The experimental data are from the Surveillance, Epidemiology, and End Results (SEER) database, not clinical cases from any medical institutions. Because the data is anonymous and the patients’ personal privacy information is not available, informed consent is not required.
Conflict-of-interest statement: The authors have no conflict of interest to declare.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Bing Chang, MD, Assistant Professor, Department of Gastroenterology, The Frist Hospital of China Medical University, No. 155 Nanjing North Street, Shenyang 110000, Liaoning Province, China. cb000216@163.com
Received: February 25, 2021
Peer-review started: February 25, 2021
First decision: May 1, 2021
Revised: May 17, 2021
Accepted: May 25, 2021
Article in press: May 25, 2021
Published online: July 26, 2021
ARTICLE HIGHLIGHTS
Research background

A nomogram is an effective tool to predict patient outcomes intuitively. Lymph node (LN) metastasis and tumor deposit (TD) conditions affect the prognosis of patients with colorectal cancer (CRC) after surgery markedly. At present, establishing an effective tool to predict the overall survival (OS) of CRC patients after surgery is necessary.

Research motivation

To establish a predictive model to assess the prognosis of CRC patients after surgery.

Research objectives

To screen out the suitable risk factors that can affect the OS of CRC patients after surgery and establish a nomogram with these factors.

Research methods

A total of 3139 patients diagnosed with CRC after surgery from the Surveillance, Epidemiology, and End Results program were divided into a training set (n = 2029) and a validation set (n = 1047) randomly. The Harrell concordance index (C-index), Akaike information criterion, and area under the curve (AUC) were used to assess the predictive efficacy of the N stage from the American Joint Committee Cancer tumor-node-metastasis classification, LN ratio, and log odds of positive lymph nodes (LODDS). Construction of the nomogram was based on the risk factors screened out through univariate and multivariate analyses. The C-index, receiver operating characteristic (ROC) curve, calibration curve, and likelihood ratio test were used to assess the final nomogram.

Research results

Seven independent predictive factors, namely, race, age at diagnosis, T stage, M stage, LODDS, TD condition, and serum carcinoembryonic antigen level, were included in the nomogram. The C-index of the nomogram for OS prediction was 0.8002 (95%CI: 0.7839-0.8165) in the training set and 0.7864 (95%CI: 0.7604-0.8124) in the validation set. The AUC values of the ROC curve predicting the 1-, 3-, and 5-year OS were 0.846, 0.841, and 0.825, respectively, in the training set and 0.823, 0.817, and 0.835, respectively, in the validation test. The final nomogram showed better sensitivity and specificity than the nomogram with N stage alone for evaluating LN metastasis in both the training set (-4668.0 vs -4688.3, P < 0.001) and the validation set (-1919.5 vs -1919.8, P < 0.001) through the likelihood ratio test.

Research conclusions

The nomogram incorporating LODDS, TD, and other risk factors shows a great predictive accuracy and better sensitivity and specificity and represents a potential tool for therapeutic decision-making.

Research perspectives

Suitable combination of LODDS and TD is necessary to simplify the nomogram. Larger sample size studies are required to include more potential risk factors, improve the nomogram, and stratify the prognosis further.